Automatic cut-out.



N0. 695,497. Patented Mar. 18, I902. A. A. SEELEY &. C. SILET. AUTOMATICCUT-OUT.

(Application filed Oct. 10, 1901.)

(No Model.) 3 Sheets-Sheet l.

6 rowul A "n "m M J I i I 1 fru eflfivzw No. 695,497. Patented Mar. l8,I902.

A. A. SEELEY &. 0. SILET.

AUTOMATIC GUT-OUT;

(Application filed Oct. 10, 1901.) (No Model.) 3 Shuts-Sheet 2.

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[Mam fi am 4 AM 1M x w I i W 7" 47725 Patented Mar. l8, I902.

A. A. SEELEY 8v. C. SILET. AUTUIATIC CUT-OUT.

(Applcat :11 d0 2 10 1901 No. 695F497.

3 Sheets-Sheet 3.

(No Model.)

51 m .Wlllil A rm SE UNITED STATES PATENT OFFICE.

AARON A. SEELEY AND CHARLES SILET, OF CHICAGO, ILLIN -(HS.

AUTOMATIC CUT-GUT.

SPECEFICATION forming part of Letters Patent No. 695,497, dated March18, 1902.

Application filed October 10, 1901. Serial No. 78.180. [No model.)

To all whom, [1' 12141.7 concern.-

Be it known that we, AARON A. SEELEY and CHARLES SILET, citizens of theUnited States, residing at Chicago, in the county of Cool: and State ofIllinois, have invented certain new and useful Improvements in AutomaticCut-Outs, of which the following is a specification.

Our invention relates to improvements in that class of devices forautomatically breaking an electric circuit whenever an excessive currententers the same and also for automatically shunting such excessivecurrent either to aground-wire or to another circuit, as may be desired,in which a fusible plug interposed in the circuit will be melted by suchexcessive current. i

In devices of the class to which our invention relates, so far as we areadvised, it is customary to interpose in the circuit a heatcoil inelectrical connection with a fusible plug, such plug being secured orattached to a portion of the structure in such a manner as to hold thesame against spring-pressure. \Vith such adevice an excessive currentpassing'through the heat-coil and fusible plug will melt the plug,thereby releasing the portion of the structure soldered or attachedthereto, whereupon such portion will be moved by spring-pressu re insuch a manner as to break the circuit. It is clear that with a device soconstructed the fusible plug must be of sufficient tensile strength tosecurely hold the portion of the device attached thereto against thespring-pressure, which tends to draw the same away from such plug. Ithas been found that for all practical purposes the softest compositionwhich may be safely and reliably used for such a plug is pure solder,which will fuse or melt at a temperature of 160. This limitation hasmade it necessary to use a heat-coil which shall oifer such a resistanceto the passage of a current exceedingin voltage the desired maximum asto generate a temperature of at least 160 within the fusible plug. Inpractice it is found that with such a device the heat-coil must offer atleast five ohms resistance, which for many purposes is sufficientlygreat to interfere seriously with the operation of the instrumentsinterposed in the circuit, especially as every circuitmust contain anumber of such heatcoils.

The primary object of our invention is to provide such a device whichshall be reliable in operation, shall offer avery low resistance, andshallbe exceedingly compact, simple, and inexpensive.

Another object of our invention is to utilize such fusible plug tooperate a trip for breaking the circuit.

A further object of our invention is to pro vide means whereby thecircuit-breaking de vice will automatically close a local circuit.

These and such other objects as may hereinafter appear are attained bythe devices illustrated in the accompanying drawings, in which Figure lis a side elevation of our device, partly in section, showing the samein set position. Fig. 2 is a like view showing the apparatus after theplug has been fused and the circuit broken. Fig. 1:} is a detail showingthe face of the contact-spring E in elevation. Fig. 2:} is a similardetail of the electrode G. Fig. 3 shows a modified form of our devicewith the plug fused and the circuit broken. Fig. 4: shows the tripmechanism of a further modification of our device with the instrument inset position. Fig. 5 is a view of the modification shown in Fig. lwiththe parts in the position occupied after the plug has been fused, themain circuit brokeinand the current shunted to the groundcircuit. Fig.(i is a detail view of our im proved heat-coil and plug. Fig. 7 is aside elevation, partly in section, of two instruments of the form shownin Fig. 3, mounted upon a common base and arranged so as to shunt thecurrent from either or both of said instruments to a common groundwire.Fig. 8 is a plan view of Fig. 7, and Fig. 9 isa view of the under sideof the base of Fig. 7.

Like letters of reference indicate the same parts in the several figuresof the drawings.

Referring by letter to the accompanying drawings, A is a base of metalor any other suitable material upon which is mounted an electrode B,which atitslowerend constitutes a binding-post upon which is mounted anut O. The electrode B is insulated from the base A by means of aniusulatinglmshing D and insulating-washer D. Also mounted on the base A,and preferably upon the bushing D, is a spring-contact E, which isinsulated from the base A and is also insulated from the electrode B,preferably by means of a shoulder D on the bushing D and aninsulating-washer F.

G is a second electrode, which is likewise V mounted upon the base A andis insulated between in the usual manner.

therefrom by means of an insulating-bushing H and an insulating-washerI, and the lower end of the electrode G constitutes a bindingpost and isprovided with a nut g. Glamped between the bushing H and a shoulder onthe electrode G and in electrical contact with the electrode G is acarbon-holder J, between which and a second holder K are held the usualcarbons j of a lightning-arrester having a perforated sheet of mica jinterposed there- The carbonholder K is secured to the base A by a boltis and nut is, said bolt constituting a bindingpost to which aground-wire may be attached. Mounted upon the electrode Gand insulatedtherefrom by means of an insulating-bushing L, an insulating-washer Z,is an electrode M, which is clamped to said bushing by a binding-post m,the washer Z, and a nut m.

' For convenience in making contact between the electrode B and thecontact-spring E we provide the electrode B with an angular portion 1),extending in the direction of the contact-springE. NormallythespringEextends in the direction of the electrode G and out of.

contact with the electrode B. By interposing the heat-coil O and plug Pbetween the electrode G and the contact-springE said contact-sprin g isthrown in electrical contact with the angular portion 1) of theelectrode B, and

at the same time the spring E and electrode G are brought intoelectrical connection with each other. The parts are so adjusted thatwhen the plug P is removed or fused the spring E, which is wedgedagainst the electrode B by means of the heat-coil O and plug P, will bereleased sufficiently to allow it to move out of contact with theelectrode B, as shown in Fig. 2.

The construction of the heat-coil O and plug P is shown in detail inFig. 6 and is as follows: 0 is a casing of insulating material and ispreferably cylindrical in form. This casing is open at one end and isprovided at the other end with aprojecting cylindrical portion 0. Theopposite end of thecasing O is closed by a metallic disk orcontact-piece Q. In the preferred form of our invention there is ametallic wire or rod R, which eX-. tends axially through the casing Oand is mounted at one end within the closed end of the casing-O. Theother end of the wire R projects through the contact-piece Q. Looselymounted upon the projecting end of the'wire R. is the fusible plug orsleeve P, which when in use is in electrical contact with the plate Q.Mounted upon the projection 0 at one end of the casing O is a metallic,washer q,

which is electrically connected withthe plate Q by means'of theheat-coil S, contained within the casing 0'.

Referring to Figs. 1% and 2%, the upper end of the spring E is providedwith an opening 6, and the upper end of the electrode Gis provided withan opening r. Whenthe heatcoil and plug are interposed between the endsof the spring E and the electrode 'G, the opening 6 in the spring Ereceives the projecting cylindrical portion 0 of the casing O, the innerface of the spring E lying against and in electrical contact with thewasher q, while the projecting end of the wire R is passed through theopening 0" in the electrode G. It will thus be seen that while theheat-coil and plug serve to wedge the spring E into electrical contactwith the electrode B, and also to electrically connect the spring E withthe electrode G, at the same time the stress of the spring E holds thespring E in electrical contact with the washer q and also holds theplate Q, the plug P, and the electrode G in contact, so as to completethe electrical connection between the spring E and the electrode G. Asso assembled it will be seen that the projecting end of the wire R isnot in contact with the electrode M, although it projects through andbeyond the electrode G. It is obvious that with a device so constructedthere is no tension at any time upon the plug P,the only requirements asto its composition'being that it shall have suflicient crushing strengthto withstand the light tension of the spring E and that it shall notfuse at the atmospheric temperature of the location where it may beplaced. It is therefore possible to use a plug which will quickly fuseat a very low temperature, and consequently we are enabled to-use aheat-coilwhich shall offer an'exceedingly low resistance.

The operation of our device when constructed as above described is asfollows:

The parts being set as shown in Fig. 1, when-v ever the potential of thecurrent passing over the main circuit shall exceed that for which theheat-coil and plug are arranged or set the heat generated by thepassage'of such excessive current through the heatcoil will result ininstantaneously melting or fusing the plug P,which,thereuponcollapsing,ceases to aid in wedging the spring E against the electrodeB. Consequently the spring E, being released, will automatically springout of contact with the electrode B, thereby breakspriug-electrodes T T,between which is a bridge U, mounted on a stem to and normally held outof contact with the electrodes T T by the spring a. Pivotally mountedupon a post V is a controlling-arm V, the free end of which n is adaptedto engage a trip \V. hen set in engagement with the trip W', thecontrolling-arm V confines the bridge U against spring-pressure betweenand in contact with the electrodes T T, the arm V being insulated fromsaid bridge by an insulatingbloek U. The trip \V is pivoted to a base WVand is provided with a rounded catch to, which engages the end 1: of thearm V, the trip XV being held in locked position by a spring m, which isinterposed between the trip W and the contact-spring E. Preferably thespring w is coiled about a headed pin or rod which is arranged to passloosely through the spring \V, as shown in Fig. 3. As in the priorconstruetion,the contact-spring E normally inclines toward the electrodeG and is wedged away therefrom and elect-rically connected therewith bythe heat-coil O and the plug P, the set position of the contact-spring Eserving also to put the spring w under sufficient stress to throw thetrip W into locking contact with the end 1) of the arm V. The terminal Tis attached to the base A by means of a screw 1', which is provided witha nut t and serves as a binding-post. The stem it of the bridge Uisprovided at its lower end with a con tact-makerrc, which when the bridgeU is released by the disengagement of the arm V from the trip W servesto connect the terminals X, thereby closing a local alarm-circuit whichmay be used to give notice of the break in the main circuit and thelocation of such break. M is a terminal for a ground-wire, one end ofsaid terminal being fitted over one of the carbons j of thelightning-arrester. WVith the device as so constructed when theapparatus is set and the circuit is closed the main circuit passes fromthe binding-post t through the terminal T, the bridge U, the terminal T,the contact-spring E, the heat-coil O, the plug P, and the electrode G.Whenever the current exceeds the predetermined maximum, the plug P isfused, as shown in Fig. 5, thereby allowing the contact-spring E toyield in the direction of the terminal G. This results in lessening thestress of the spring in, thereby releasing the arm V from the trip W,the upward pressure of the insulating-block U against the under side ofthe arm V assisting in disengaging the arm V from the trip W. As soon asthe arm V is released the bridge U is thrown upwardly and disengaged bythe spring a from the electrodes T T, thereby breaking the main circuit.At the same time the contactmaker 50 is drawn into contact with theterminals X, thereby bridging the same and closing a local circuit. Ifit be desired to at the same time shunt the main current into anotherwire otherwise than by means of the usual lightning-arrestcr, the devicewill be fitted with the electrode h with which the wire R makes directcontact when the plug P is fused and the spring E moves in the directionof the electrode G.

There a number of automatic cut-out devices are desired at a givenpoint, they may be compactly mounted in pairs, as shown in Fig. 7, inwhich two of our devices of the form shown in Fig. 3 are mounted upon acommon base, each of said devices being interposed in a separate circuitfrom the other device; but whenever circuit is broken the current willbe shunted to the same ground-wire. This arrangement in pairs can ofcourse also be made with the preferred form of our device, as shown in.Figs. 1 and 2.

Aside from the advantages previously noted it will also be seen thatwith our improved device it is impossible for an excessive current toinjure the instruments which are protected by our automatic cut-out.Further, whenever the circuit is broken by an excessive current no partof the device except the fusible plug P needs to be renewed, and as thisplug can be made in the form of a sleeve, which is merely slipped overthe wire R, the fused plugs can be readily replaced at practically noexpense and with a minimum of delay and labor. So, also, as the casing Oand attached parts need be held in engagement with the spring E andelectrode G only by springpressureit is a simple matter to keep on handa number of the heat-coils complete, including the casing O and attachedparts, in which the heat-coils proper shall afford any desiredresistance. lVith such a supply on hand it is only the work of aninstant to remove any given heat-coil and plug from our apparatus andreplace it with one affording any desired resistance.

While we have described our preferred c011- structions,there are manymodifications which may be made as a matter of convenience or of shopexpediency, but which do not involve a departure from the spirit of ourinvention. Obviously the contour and proportions of many of the partsmay be varied considerably and parts not needed fora given service maybe omitted, as convenience or expediency may suggest, without departingfrom the spirit of our invention.

\Vhile we have shown and described our invention as an automaticcut-out, our combination of the heat-coil and fusible plug with a pairof electrodes, one at least of said electrodes being spring-aetuated insuch a manner that said electrodes are wedged apart by the fusible plugthrough which the circuit is completed and movement of thespring-actuated electrode is permitted whenever the plug is fused by anexcessive current, thereby narrowing the wedge, is suitable for use inany situation and for any purpose where it is desired that theintroduction of an excessively strong current into the circuit shallresult in the movement of a portion of the apparatus, whether suchmovement be used to operate a switch for wholly or in part shunting thecurrent or to operate a trip for breaking the circuit or for opening avalve or for any other usual purpose.

Having thus described our invention, what we claim, and desire to secureby Letters Patent, is-

1. The combination with an electric circuit, of a pair of electrodes, afusible plug interposed therebctween, means interposed in said circuitfor automatically fusing said plug, and means for automatically movingone of said electrodes in the direction of the other electrode wheneversaid plug is fused.

2. The combination with an electric circuit,

of a spring-contact, an electrode, a fusible plug interposed in saidcircuit between said spring-contact and said electrode so as to deflectsaid spring-contact against spring-pressure, and means interposed insaid circuit for automatically fusing said plug.

I 3. The combination with an electric circuit, of a pair of electrodes,a wedge interposed between said electrodes, said wedge comprising afusible plug, and means for completing said circuit between saidelectrodes, means for automatically f using said plug, and means forautomatically deflecting one of said electrodes in the direction of theother electrode whenever said plug is fused.

4. The combination with an electric circuit,

' of a pair of electrodes, a wedge interposed said plug and means forautomatically throwbetween said electrodes and completing said circuit,said wedge comprising a' heat-coil, contacts and a fusible plug, andmeans for automatically moving one of said electrodes in the directionof the other electrode whenever said plug is fused.

5. The combination with an electric'circuit, of a pair of electrodes, acontact-maker, a wedge interposed between said contact-maker and one ofsaid electrodes so as to hold said contact-maker in contact with theother of said electrodes, said wedge comprising a fusible plug, meansfor automatically fusing ing said contact-maker out of contact wheneversaid plug is fused, substantially as described.

6. In an automatic cut-out device, the combination with a pair ofelectrodes, of a springcontact arranged to make contact with one of saidelectrodes, but normally out of contact therewith, a circuit-closingdevice comprising a fusible plug interposed between said spring-contactand one of said electrodes so as to force said spring-contact intocontact with the other of said electrodes, .and means for automaticallyfusing said fusible plug, substantially as described.

7. The combination with an electric circuit, of a pair of electrodes, acontact-maker arranged to make contact with one of said electrodes butnormally outof con tact therewith, a fusible plug interposed between theother of said electrodes and said contact=maker so as to force saidcontact-maker into. contact with the first-mentioned electrode, meansfor automatically fusing said plug and-releasing said contact-maker, andmeans actuated-by themovement of said contact-maker, when so released,for automatically closing a second circuit.

8. In an automatic cut-out device, the combination with aspring-electrode, of a fusible plug interposed between saidspringelectrode and a stationary part of the device so -as to force saidspring-electrode out of its normal position and complete said circuit,means for automatically fusing said plug, and means, set in motion uponthe release of said springelectrode, for breaking said circuit,substantially as described.

9. In an automatic cut-out device, the combination with aspringelectrode, of a fusible plug interposed between saidspring-electrode and a stationary part of the device so as to completesaid circuit and force said springelectrode out of its normal position,means forautomatically fusing said plug,and means, set in motion uponthe release of said springelectrode, for breaking said circuit and forclosing a second and independent circuit, substantially as described.

10. In an automatic cut-outdevice,the combination with aspring-electrode, of a fusible plug interposed between saidspring-electrode and a stationary part of the device so as to completesaid circuit and force said springelectrode out of its normal position,means for automaticallyfusing said plug,and means, set in motion uponthe releaseof said springelectrode, for breaking said circuit and forclosing a shunt-circuit, substantially as described.

11. Inacircuitbreakingandclosingdevice, the combination with a pair ofelectrodes, of a contact-maker arranged to make contact with one of saidelectrodes but normally out of contact therewith, a circuit-closingdevice comprising a fusible plug interposed between said contact-makerand the other of said electrodes so as to force said contact-maker intocontact with the first-mention ed electrode, means for automaticallyfusing said plug, a third electrode, and means actuated by the movementof said contact-maker upon the fusing of said plug for electricallyconnecting said third electrode with one of the aforesaid electrodes,substantially as described.

12. In an automatic cut-out'device, the combination with aspring-electrode, of a fusible plug interposed between saidspring-electrode and a stationary part of the device so as to completesaid circuit and force said springelectrode out of its normal position,means for automatically fusing said plug, and means, set in motion uponthe release of said springelectrode, for breaking said circuit, closinga shunt-circuit and also closing an independent circuit, substantiallyas described.

13. In an automatic cut-out device, the combination with aspring-electrode, of a fusible plug interposed between saidspring-electrode and a stationary portion of the device so as to forcesaid spring-electrode out of its normal position, means forautomatically fusing said plug, a trip automatically operated by themovement of said spring-electrode when released, an arm engaged by saidtrip, a pair of electrodes, a circuit closing bridge arrangedtherebetween and held by said arm in contact with said pair ofelectrodes, and means for automatically throwing said bridge out ofcontact with said pair of electrodes upon the release of said arm,substantially as described.

14. A circuit-closing plug comprising a cell formed of insulatingmaterial, a heat-coil arranged Within said cell, an exposed metalliccontact arranged at each end of said heat-coil, and a loose fusible plugarranged adjacent to one of said metallic contacts.

15. A circuit-closing plug comprisinga cell made of insulating materialand provided at one end with a projection of like material, a heat-coilarranged Within said cell, a metallic contact mounted upon saidprojection and electrically connected with one end of said heat-coil, anexposed metallic contact electrically connected with the other end ofsaid heat-coil, and a fusible plug arranged externally of said cell andadjacent to said metallic contact.

16. lhe combination with an electric circuit, of a freely-removablefusible plug interposed therein to complete said circuit, and means forautomatically fusing said plug, said means being adapted to be operatedby the entrance of an excessive current to said circuit, substantiallyas described.

17. The combination With an electric circuit, of a pair of contacts anda fusible plug forming a part of said circuit and interposed between oneof said contacts and another portion of the apparatus, so as-to completesaid circuit by deflecting one of said contacts into electrical contactwith the other of said contacts, substantially as described.

AARON A. SEELEY. CHARLES SILET. lVitnesses:

M. E. SHIELDS, E. Y. GRIDLEY.

